Power converters and in particular switched mode power converters typically make use of one or more power switches which are commutated between an on-state and an off-state in an alternating manner at a commutation cycle rate. The one or more power switches may be controlled in dependence of the current flowing through the one or more power switches. By way of example, a power switch may be commutated from an on-state to an off-state, subject to the detection that the current through the power switch has reached a pre-determined peak current.
In order to be able to accurately control the states of a power switch based on the current flowing through the power switch, current measurement means are desirable which are configured to provide an accurate indication of the current flowing through the power switch. Such an indication should be substantially independent of the operational conditions of the power switch, such as the temperature and/or the supply voltage at which the power switch is operated. The present document describes such current measurement means (also referred to herein as current sensing circuits).